Tests on an early model 5G phone in the US yielded some good news and some bad news.
5G or fifth-generation mobile networks offer blazingly fast speed - if you've got a phone that supports the technology.
The first 5G networks are being rolled out in the US and Australia now (if initially restricted to a handful of inner city areas). Here, Spark, Vodafone and 2degrees could begin 5G upgrades sometime next year, if radio spectrum auction details (complicated by iwi claims) get sorted on schedule.
The good news
After using 5G across multiple phone US networks, the Wall Street Journal's Joanna Stern reported, "5G is fasten-your-seat-belt fast … I downloaded the whole new season of "Stranger Things" from Netflix in 34 seconds. The same averaged more than an hour on my 4G connections."
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In part, Stern enjoyed superfast mobile because she was one of the first 5G users in the US - which is akin to being one of the only drivers on a new stretch of motorway.
But 5G has so much bandwidth to burn that even after the hordes pile on, it should still offer speed on a par with a landline fibre connection - and none of the latency or lag problem that bedevils 4G with some data-intensive two way connections like gaming or videoconferencing.
The bad news
"One of my key findings? Samsung's Galaxy S10 5G, one of the first 5G phones, doesn't work reliably when it's above 80-or-so degrees [27C]," Stern wrote.
"While running a download test or two, the phone would overheat and sever the 5G signal, leaving me with a 4G connection. I had to get creative chilling out my test phones. Yes, ice coolers."
She said cellular carriers running demos of the phone had also resorted to ice packs or air conditioning.
The S10 chops down from 5G to 4G when the temperature reaches a certain threshold to minimise energy use and optimise battery, a Samsung spokeswoman said.
"As 5G technology and the ecosystem evolve, it's only going to get better," she added.
Stern's conclusion: while 5G is "knock your socks off fast", like Version 1.0 of any new technology, it will take a little time for all the kinks to be worked out.
So, (sorry, Simon) it's probably not worth stressing that Kiwi telcos won't begin their rollouts until next year sometime.
No, it won't fry your brain
An early 5G phone over-heating is, inevitably, going to fire-up the "cellphone radiation" conspiracy crowd.
But as scientist Michelle Dickinson explained in one of her recent Herald columns, mobile phones and mobile networks are safe.
I'm constantly encountering people - including many who should know better - telling me 4G and 5G scare stories, so it's worth quoting her at length. "Nanogirl" said, in part:
"The frequencies we refer to in mobile phone technology are all radio signals, and often referred to as RF or Radiofrequency radiation. For most people, anything with the word radiation in it sounds scary. It's not as intimidating as it might seem though - the word just means the emission of energy from any source.
"Too much exposure to radiation is thought to be bad for us, and linked to cancer. This is why we are advised to limit the number of medical x-rays we have a year. X-rays are a form of ionising radiation, and repeated exposure has been seen to damage our DNA, which over time has been shown to increase the risks of developing cancer.
"Radiation is split into two broad categories: ionising and non-ionising. Non-ionising radiation doesn't carry enough energy to 'ionise' or strip electrons from atoms and molecules. It therefore doesn't have enough energy to damage our DNA.
"The radiation emitted from radios, mobile phones, phone towers and Wi-Fi routers – RF radiation - is non-ionising."
At this point, the social media mob will be saying, "Ah - but 5G is much more powerful than 4G!"
To this, Dickinson says, "As the frequency goes up, the depth of penetration into biological tissues goes down. This means that 5G is even less likely to penetrate the body than the current technology that we use, so no need to invest in a new tinfoil hat."
And tech commentatory Paul Brislen - a cancer survivor himself - has noted that no "cellphone spike" has come through in Ministry of Health statistics.
He's right. The incidence of brain cancer in New Zealand actually dropped slightly (from 185 per 100,000 of the population to 172/100,000) over the first three years of 4G mobile networks' operation. And while some cancers have spiked (notably melanoma), cancer rates overall are slightly down on the mid-1990s, when cellphones went mainstream.
Still, the mob keeps braying. There's irony in the idiocy, too.
School kids who are chased away from "dangerous" wi-fi routers in classrooms to play in the "healthy" sunshine are actually being shepherded from harmless non-ionising radiation to harmful solar radiation.
(Hold your letters. There are lots of good reasons for playing outdoors, if you're properly protected.)
The social media-driven fake news cycle being what it is, there'll be a lot more 5G scaretalk over the next 12 months. Maybe I'll put on a tinfoil hat, too, and pull it down over my eyes.